2.  Unit : nucleotides
-macromolecules which store genetic
information in the form of a code
• -diagram of nucleic acid
Phosphate
group
Pentose Nitrogenous
sugar
base

3. Deoxyribonucleic acid (DNA) Ribonucleic acid (RNA)
Consists of two polynucleotides consists of a single-stranded
strands twisted around each nucleotide , which may be
other in the form of a double folded back on itself
helix
found in the nucleus Found in the nucleus
, mitochondrion and , cytoplasm and ribosomes
chloroplast
importance : carries genetic Importance : three types of RNA
code. Its structure allows it to are involved in protein synthesis.
store genetic information and RNA is also the genetic material of
some viruses
pass the genetic code to new
cells

4.  Importance of nucleic acid: store and
transmit hereditary(genetic) information
 Made up of chemical elements carbon ,
hydrogen and oxygen
 The ratio of hydrogen atoms to oxygen
atoms is 2:1

5. Types monosaccharide disaccharide polysaccharide
Example Glucose , fructose Maltose , sucrose Starch , glycogen
, galactose , lactose , cellulose
Molecular C6H12O6 C12H22O11 (C6H10O5)N , N
formula varies from 40 to
several thousands
Taste Sweet Sweet Not sweet
Solubility in water Soluble Soluble Insoluble
Reducing sugar Yes Maltose , lactose- No
yes
Sucrose- no
Conformation test Benedict’s Benedict’s Iodine turns to
solution turns to solution remains blue-black
brick-red unchanged
precipitate

6. Glucose + glucose < > condensation / hydrolysis < > maltose + water

7. Polysaccharides + water < > hydrolysis < > monosaccharides

8.  Made up of elements carbon , hydrogen
, oxygen , nitrogen
 Unit : monomers or amino acids
 Some protein contain sulphur and
phosphorus

9. Amino acid + amino acid < > condensation / hydrolysis
< > dipeptides + water

10. Polypeptides + water hydrolysis dipeptides or amino acids

11.  Structures of protein
-the sequence of amino acid in a
polypeptide

12.  Secondary structure
-the coiling and folding of polypeptide
chain by hydrogen bonds

13.  Tertiary structure
-the overall three-dimensional shape of a
polypeptide chain
-examples:
enzymes,hormones,antibodies,plasma protein

14.  Quarternary structure
-the combination of two or more tertiary
polypeptides that makes up a protein
-example : haemoglobin

15. Essential amino acids Non-essential amino acids
• Amino acids hat cannot • Are amino acids that can
be synthesised by the be synthesised by the
body body
• Can be obtain from the • Derived from other amino
diet acids
• Leucine is an example • There are 11 non-essential
• There are altogether 9 amino acids
essential amino acids • Plant protein do not
• Animal proteins contains contain all the essential
all the essential amino protein (they are called
acids (they are called first second class protein)
class proteins)

16. elastin, collagen, and Structural functions in support
keratin
ovalbumin and casein Storage food source
haemoglobin and cell Transport moves other substances
membrane proteins
amylase and proteases Enzymes aid in chemical
reactions
actin and myosin Contractile movement

17.  Made up of elements carbon , hydrogen , oxygen
 Ratio of hydrogen atoms to oxygen atoms in one
molecule of lipids is much higher then the 2:1 ratio
in carbohydrates
 Percentage of oxygen in lipids is lower than in
carbohydrates
 Some lipids have nitrogen and phosphorus
 Lipids are insoluble in water but soluble in other
lipids and organic solvent such as alcohol and
ether

18. Types Examples Functions
Triglycerides fats: butter, lard Energy storage
oils: cooking oil
Steroids medicines or estrogen or Regulate metabolism,
testosterone immune response,
reproduction and other
essential biological
processes,
Waxes Candle Fuel sorce

20. Saturated fats Differences Unsaturated fats
Absent Presence of double Have at least one
bonds between carbon double bond
atoms in fatty acids
Bonded with maximum Ability to react with an Not bonded with
number of hydrogen additional hydrogen maximum number of
atoms atom hydrogen atoms
Solid Condition at room Liquid
temperature
Butter Examples Corn oil